EURion constellation

- updated 2018/12/14 16:12

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The EURion constellation is made up of five rings.

The EURion constellation (also known as Omron rings[1] or doughnuts[2]) is a pattern of symbols incorporated into a number of banknote designs worldwide since about 1996. It is added to help imaging software detect the presence of a banknote in a digital image. Such software can then block the user from reproducing banknotes to prevent counterfeiting using colour photocopiers. According to research from 2004, the EURion constellation is used for colour photocopiers but probably not used in computer software.[3] It has been reported that Adobe Photoshop will not allow editing of an image of a banknote, but this is believed to be due to a different, unknown digital watermark rather than the EURion constellation.[4][3]

The EURion constellation first described by Kuhn consists of a pattern of five small yellow, green or orange circles, which is repeated across areas of the banknote at different orientations. The mere presence of five of these circles on a page is sufficient for some colour photocopiers to refuse processing.

Some banks integrate the constellation tightly with the remaining design of the note. On 50 DM German banknotes, the EURion circles formed the innermost circles in a background pattern of fine concentric circles. On the front of former Bank of England Elgar £20 notes, they appear as green heads of musical notes; however, on the Smith £20 notes of 2007 the circles merely cluster around the "£20" text. On some U.S. bills, they appear as the digit zero in small, yellow numbers matching the value of the note. On Japanese yen, these circles sometimes appear as flowers.

Technical details regarding the EURion constellation are kept secret by its inventors and users.[2] A 1995 patent application[6] suggests that the pattern and detection algorithm were designed at Omron Corporation, a Japanese electronics company. It is also not clear whether the feature has any official name. The term "Omron anti-photocopying feature" appeared in an August 2005 press release by the Reserve Bank of India.[7] In 2007 the term "Omron rings" was used in an award announcement by a banknote collectors society.[8]

See also

Coded anti-piracy, an anti–copyright-infringement technology which marks each film print of a motion picture with a distinguishing patterns of dots, used as a forensic identifier to identify the source of illegal copies